Those investing credibility in the concept of “junk DNA” suffered more losses this week. Repeated hits to the paradigm that portions of non-coding DNA are useless leftovers of evolution make a recovery unlikely. In Science,1 researchers from Princeton and Indiana University reported a function for transposons and the genes that act on them, “previously considered selfish DNA or part of the dispensable genome.” A small eukaryote microbe uses enzymes called transposases extensively during development. “Through an exaggerated process of genome rearrangement, Oxytricha trifallax destroys 95% of its germline genome during development,” they said, resulting in the elimination of all transposon DNA. What’s going on? “We show that transposase gene expression occurs during germline-soma differentiation and that silencing of transposase by RNA interference leads to abnormal DNA rearrangement in the offspring,” they said. “This study suggests a new important role in Oxytricha for this large portion of genomic DNA that was previously thought of as junk.”Update 05/20/2009: PhysOrg reported on this paper and said, “researchers from Princeton University and Indiana University who have been studying the genome of a pond organism have found that junk DNA may not be so junky after all. They have discovered that DNA sequences from regions of what had been viewed as the ‘dispensable genome’ are actually performing functions that are central for the organism.” At the end of the article, PhysOrg said, “The term ‘junk DNA’ was originally coined to refer to a region of DNA that contained no genetic information. Scientists are beginning to find, however, that much of this so-called junk plays important roles in the regulation of gene activity. No one yet knows how extensive that role may be.” Another press release from Rockefeller University upset a common idea about micro-RNAs, those ubiquitous little snippets of RNA that have been found to play many important roles in the cell. Some of these microRNAs are highly conserved (i.e., unevolved) between distant life-forms. The assumption has been that they play similar roles; “The na?ve assumption is that if we understand what these microRNAs do in a fish or in the frog, we can extrapolate to humans,” Ali H. Brivanlou, the head of the embryology department, said. That assumption appears to be flawed. They found that the counterpart in humans targets different activator proteins.personify evolution as a bumbling yet personal inventor:“When evolution has lucked into efficient solutions for life’s most fundamental problems, it adopts them as invaluable family heirlooms, passing them down as one species evolves into another.”“Although the microRNAs are evolutionarily conserved, their target changes across species,” said Brivanlou. “These are genetic tools that nature has invented, much like the screwdriver, to build different things for different species.” 1. Nowacki et al, “A Functional Role for Transposases in a Large Eukaryotic Genome,” Science, 15 May 2009: Vol. 324. no. 5929, pp. 935-938, DOI: 10.1126/science.1170023.Replacing one myth with another is not progress. Junk DNA is a Darwinian myth that intelligent design theory could have prevented. Geneticists looking through their Darwin-tinted glasses have misinterpreted the genome, because they expected to find waste and disorder. An ID geneticist would face the problem differently: we don’t understand what the microRNAs and non-coding DNA segments are doing; therefore, we will discover what they are there for. The Darwinists have not learned their lesson. Instead, they are retreating into their usual Charlie & Tinker Bell fairy tale. Tinker Bell zaps genes with her mutation wand, and Charlie, the bumbling junkyard engineer, looks for scraps to cobble together into family heirlooms. This adds the fallacies of naive assumptions [i.e., glittering generalies] and extrapolation to their logical sins. It takes intelligence to invent a tool and use it for multiple functions.(Visited 11 times, 1 visits today)FacebookTwitterPinterestSave分享0
The browser is a beautiful thing, but it can be made so much better with the right tools. In the screenshot posted here, you can see new two tools in action – both of which you should check out right away. What you’re looking at in that image is the page for a single Tweet, viewed using the brand new Chrome browser extension from Embed.ly, which displays embedded previews from 165 different publishing platforms and previews of any web link posted on Twitter. It’s a must-have. Overlayed on top of that? The rapid sharing tool Cortex – probably the fastest way to post links to Twitter, Facebook, Instapaper and Tumblr. Click your mouse, hold for two seconds and that circle shows up. Move over one of the sections and you’re on your way to sharing a link.Embedly makes beautiful use of web standards. Cortex is still a little rough around the edges; it could use a character count-down for Twitter, for example, and it takes some getting used to before it’s easy to control. It’s worth trying for a while, though.What’s the third? ReadOn.ly, a simple little bookmarklet that makes it easy to share links with fly-out quotes and tags that can be navigated to view all the most interesting quotes on a given topic found by other users. It’s a really cool little service. There are others like it, see Sniply, for example, and each of them brings a different design element to the nascent field of content curation. There’s clearly a whole lot of room for development in the field of curation and sharing. Top Reasons to Go With Managed WordPress Hosting A Web Developer’s New Best Friend is the AI Wai… marshall kirkpatrick Related Posts 8 Best WordPress Hosting Solutions on the Market Why Tech Companies Need Simpler Terms of Servic… Tags:#Product Reviews#web
The big mystery of the BJP-Shiv Sena alliance — how many seats each party will get and who will get more — may have shifted focus from the clout of Chief Minister Devendra Fadnavis in the Maharashtra unit of the BJP. Last week, however, as some spurts of rebellion arose in the Mumbai unit following the finalisation of some city seats, the true extent of Mr. Fadnavis’ dominance of the party in his State, a five-year project, was revealed.The list of candidates released by the Maharashtra BJP saw the sidelining of several bigwigs, many of whose relations with Mr. Fadnavis had soured of late. The fact that the high command in Delhi backed him fully on the list, though some of those replaced (like Ghatkopar MLA Prakash Mehta) are considered close to Union Home Minister Amit Shah, is significant.Eased outOne of the biggest names to be excluded was Education Minister Vinod Tawde, who was denied ticket from Borivili, one of the safest seats for the BJP. Relations between Mr. Fadnavis and Mr. Tawde have not exactly been rosy since 2014, when the former became a surprise choice of Chief Minister. The seat was given to Sunil Rane, considered close to both Mr. Fadnavis and Union Roads and Highways Minister Nitin Gadkari, ensuring that the latter too provided support to the candidate, in the face of obvious hurt feeling among Mr. Tawde’s supporters.Within Mumbai, the choices for Colaba (replacing sitting MLA and local strongman Raj Purohit with Nationalist Congress Party turncoat Rahul Narvekar) and Ghatkopar East (replacing veteran Prakash Mehta with Parag Shah) were decisions that led to much heartburn and even some acts of violence by supporters of Mr. Mehta.Mr. Rajpurohit, considered a strong leader with his origins in Rajasthan, had embarrassed the Fadnavis government with certain utterances. His replacement with Mr. Narvekar, who has only recently joined the BJP from the NCP, however was the blow that hurt the most, according to his supporters.BJP sources, however, say Mr. Narvekar is the perfect replacement not just because his brother Makarand Narvekar is a BJP corporator but more importantly because he is the son-in-law of Ramraje Naik Nimalkar, senior NCP leader and Chairperson of the Maharashtra Legislative Council. “Nimbalkar is one of the biggest supporters for [NCP leader] Sharad Pawar, and this move has neutralised an aggressive NCP move on that seat,” a BJP source said.In Mr. Mehta’s case, it was a relationship that began on a promising note with Mr. Fadnavis being helped by the former to move into the late Gopinath Munde’s turf, turning sour after 2016-17 when certain corruption allegations were levelled against Mr. Mehta who was Housing Minister. Considered a strong leader among the city’s Gujarati community, he has been replaced by young gun Parag Shah.The most tricky replacement was that of Jalgaon strongman Eknath Khadse, who was placated after ticket was given to his daughter, Rohini Khadse-Khewalkar, instead.In one fell swoop, there has been a generational and factional shift in the Maharashtra BJP. Mr. Fadnavis has stamped his authority on the Maharashtra BJP.